The present invention relates to a micro-manipulator, and particularly to a micro-manipulator provided with a handling mechanism for gripping a micro-material with two gripping fingers.
Conventionally, a micro-manipulator is used for assembling a micro-component and handling a cell. Generally, in order to grip a micro-material, a micro-manipulator has a mechanism for driving (handling mechanism) gripping fingers for handling the micro-material. (See Japanese Patent Publication Kokai No. 08-168979.) Working via a micro-manipulator generally requires viewing the micro-material through a microscope with the naked eye, or viewing an image output to a display via a CCD camera mounted on a microscope. (See Japanese Patent Publication Kokai No. 04-303810.)
As shown in FIGS. 10A to 10C, end effecters 11 and 12 that touch the micro-material in the two gripping fingers are equipped on a conventional micro-manipulator having such a mechanism. A handling mechanism operates so that the positions of the end effecters 11 and 12 have an equal distance to the micro-material 10. The two gripping fingers simultaneously move toward each other to grip the micro-material 10.
To align each of the leading ends of the two gripping fingers (the end effecters), technology is known for preventing mis-positioning caused by assembling two gripping fingers composed of one elastic member. (See the example in 2004 Precision Engineering Spring Engineering Lecture Bulletin L76.)
However, as shown in FIGS. 10A to 10C, if the positions of the end effecters 11 and 12 are not at equal distances from the micro-material 10, the side of the end effecters closest to the micro-material will come into contact with the micro-material first and push the material toward the other side. If the action for gripping of the end effecters follows a circular locus, the gripping position will be incorrect with regard to the micro-material. Thus, it will be impossible for the end effecters to properly grip the material. (See FIGS. 10D and 10E.)
To avoid this situation, each of the two gripping fingers is independently driven. Therefore, it is necessary to correct phase and time differences that can exist between the two independently driven fingers. This requires the addition of an actuator or clutching mechanism, or other additional mechanisms, which also adds to the difficulty of operation.
Furthermore, there is a limit to the materials that can be used to configure two gripping fingers using one elastic member, and high forming precision has been required. To avoid that situation, the dimensional tolerance must be held down when the gripping fingers and end effecters are composed of a plurality of parts.
Thus, in view of the aforementioned technologies, the present invention provides a micro-manipulator that securely and rapidly grips micro-material within the field of view of a microscope.
Further objects and advantages of the invention will be apparent from the following description of the invention and the associated drawings.